Adding enque time tracking and logging

Motivation:
  - Currently we have 2 seperate monkey patches in place for tracking
  enqueded time for 2 seperate workers. It seems that activejob could be
  a source of truth for how long an item has been enqued so that we can
  easily use it for consistent monitoring across workers/apps to ensure
  that jobs are running at an acceptable speed.

Changes:
  - Add an enqueded at attribute and serilization tooling.
  - Add a method to get how long a job has been enqueded for.
  - Add a logging item to show how long a job was enqued prior to the
  perform method firing.

2 files changed, 13 insertions, 0 deletions

diff --git a/activejob/test/cases/job_serialization_test.rb b/activejob/test/cases/job_serialization_test.rb
index 86f3651564..c1cec1f1d6 100644
--- a/activejob/test/cases/job_serialization_test.rb
+++ b/activejob/test/cases/job_serialization_test.rb
@@ -61,4 +61,15 @@ class JobSerializationTest < ActiveSupport::TestCase
       assert_equal "Hawaii", job.serialize["timezone"]
     end
   end
+
+  test "serialize stores the enqueued_at time" do
+    h1 = HelloJob.new
+    type = h1.serialize["enqueued_at"].class
+    assert_equal String, type
+
+    h2 = HelloJob.deserialize(h1.serialize)
+    # We should be able to parse a timestamp
+    type = Time.parse(h2.enqueued_at).class
+    assert_equal Time, type
+  end
 end
diff --git a/activejob/test/cases/logging_test.rb b/activejob/test/cases/logging_test.rb
index 6154ba301d..acd37456c9 100644
--- a/activejob/test/cases/logging_test.rb
+++ b/activejob/test/cases/logging_test.rb
@@ -115,6 +115,8 @@ class LoggingTest < ActiveSupport::TestCase
     perform_enqueued_jobs do
       LoggingJob.perform_later "Dummy"
       assert_match(/Performing LoggingJob \(Job ID: .*?\) from .*? with arguments:.*Dummy/, @logger.messages)
+
+      assert_match(/enqueued at /, @logger.messages)
       assert_match(/Dummy, here is it: Dummy/, @logger.messages)
       assert_match(/Performed LoggingJob \(Job ID: .*?\) from .*? in .*ms/, @logger.messages)
     end